US4953038A - System including a CCD imager device for reading a storage phosphor record carrier - Google Patents

System including a CCD imager device for reading a storage phosphor record carrier Download PDF

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Publication number
US4953038A
US4953038A US07/236,575 US23657588A US4953038A US 4953038 A US4953038 A US 4953038A US 23657588 A US23657588 A US 23657588A US 4953038 A US4953038 A US 4953038A
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US
United States
Prior art keywords
record carrier
light source
carrier
image pick
ccd image
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US07/236,575
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English (en)
Inventor
Ulrich Schiebel
Walter Hillen
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US Philips Corp
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US Philips Corp
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Assigned to U.S. PHILIPS CORPORATION, 100 EAST 42ND STREET, NEW YORK, N.Y. 10017, A CORP. OF DE. reassignment U.S. PHILIPS CORPORATION, 100 EAST 42ND STREET, NEW YORK, N.Y. 10017, A CORP. OF DE. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: HILLEN, WALTER, SCHIEBEL, ULRICH
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
    • G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
    • G01T1/16—Measuring radiation intensity
    • G01T1/20—Measuring radiation intensity with scintillation detectors
    • G01T1/2012—Measuring radiation intensity with scintillation detectors using stimulable phosphors, e.g. stimulable phosphor sheets
    • G01T1/2014—Reading out of stimulable sheets, e.g. latent image

Definitions

  • the invention relates to a device for reading a storage-phosphor record carrier, comprising a light source which is arranged at one side of the record carrier for optical stimulation of the storage phosphor, a photodetector device which is arranged at the other side of the record carrier for conversion into an electric signal of fluorescent light generated by stimulation of the phosphor, and a drive device for realizing a relative displacement between the record carrier on the one side and the light source and the photodetector device on the other side.
  • a device of this kind is known from EP-OS 01 67 747.
  • the light source thereof is formed by a row of, for example light-emitting diodes, the detector device consisting of correspondingly arranged photodiodes.
  • the light-emitting diodes are successively switched on, so that the photodiodes successively convert the fluorescent light, formed one point after the other, into an electric signal.
  • the light source and the photodetector device are displaced relative to the record carrier, i.e. first in a first direction perpendicular to the row direction, and subsequently in a second direction which is perpendicular thereto. Because reading is sequential, the read times are comparatively long.
  • the light source illuminates a sub-surface which consists of a plurality of pixels
  • the photodetector device comprising a CCD image pick-up device which covers the illuminated sub-surface and which is arranged and controlled so that the charges in the cells of the CCD image pick-up device are transported in the same direction and at the same speed as the sub-surface illuminated by the light source is displaced on the record carrier.
  • the illumination and reading of the pixels of the sub-surface is performed simultaneously. Because of the relative displacement between the record carrier and the light source as well as the photodetector device, the illuminated and read sub-surface moves across the record carrier. In order to achieve a sufficiently high signal-to-noise ratio, charges in the cells of the CCD image pick-up device, converting the fluorescent image produced by stimulation into an electric signal, are transported in the indicated manner so that the image information originating from a pixel during its stimulation is integrated.
  • the signal-to-noise ratio being limited by the given sensitivity of the CCD image pick-up device, can be further improved in a further embodiment of the invention in that the detector device comprises an image intensifier which is arranged between the record carrier and the CCD image pick-up device and which images the fluorescent image produced on the storage phosphor record carrier onto the CCD image pick-up device.
  • the image intensifier thus increases the luminescent density of the fluorescent image before it is converted into an electric signal by the image pick-up device.
  • the CCD image pick-up device comprises a plurality of CCD image pick-up devices which are adjacent arranged perpendicularly to the displacement direction.
  • the light source is formed by a low-pressure sodium discharge lamp.
  • Low-pressure sodium discharge lamps have a very high radiation density, notably in the wavelength range which is of essential importance for the stimulation of storage phosphors.
  • FIG. 1 diagrammatically illustrates an embodiment of the invention
  • FIG. 2 shows a CCD image pick-up device and a charge transport therein
  • FIG. 3 shows a part of a CCD device for such an image device claimed in claim 1.
  • the storage phosphor record carrier whose principal dimension extends perpendicularly to the plane of drawing of FIG. 1 consists of a transparent substrate 2 on which there is provided a layer of storage phosphor 1, for example as described in U.S.-PS 4 369 367.
  • the record carrier 1, 2 is situated in a read station in which it is transported, preferably at a constant speed, in the direction of the arrow by means of transport rollers 10, 13 and conveyor belts 11.
  • a tubular light source 3 which illuminates a sub-surface area of the record carrier 1, 2 via a cylindrical lens 4 and through the aperture of a diaphram 5, thus stimulating the storage phosphor present thereon.
  • the principal dimension of the light source 3, the cylindrical lens 4 and the diaphram 5 extends perpendicularly to the plane of drawing, preferably across the entire width of the record carrier 1, 2.
  • the light source is preferably formed by a low-pressure sodium discharge lamp whose light is in the optimum wavelength range for the stimulation of the storage phosphor. As a result, a plurality of adjacent pixels are illuminated simultaneously in a two-dimensional array from right to left in the drawing and into the plane of the drawing.
  • the fluorescent image produced by stimulation is imaged onto the photocathode of an image intensifier 7 by means of an optical fibre plate 6, for this purpose the photocathode is preferably provided directly on the optical fibre plate.
  • a filter (not shown) which suppresses all radiation whose wavelength does not correspond to the wavelength of the fluorescent light.
  • the exit image of the image intensifier 8 is transferred to the input of a CCD image pick-up device by means of an optical fibre system.
  • a CCD image pick-up device represents an integrated circuit having comparatively small dimensions, in the direction perpendicular to the plane of drawing there are provided a number of optical fibre segments 8, 8', each of which comprises a CCD image pick-up element 9, 9'.
  • the neighbouring segments 8, 8' are preferably inclined towards one another, so that the CCD image pick-up elements 9, 9' whose optically active surfaces are always smaller than their dimensions cannot contact one another, at their ends which are remote from the image intensifier 7.
  • FIG. 2 diagrammatically shows an image pick-up element. It consists of a plurality of transfer channels 92, each of which consists of a number of photosensitive charge-coupled cells. These CCD image pick-up elements are mounted on the fibre optical segments 8, 8' so that the direction of their channels 92 coincides with the displacement direction of the storage phosphor record carrier 1, 2.
  • the read rate for the CCD image pick-up elements is chosen so that the charge is transferred through the transfer channel from one cell to another at the same speed as that at which the image of a pixel on the storage phosphor record carrier 1, 2 is displaced due to the displacement of the record carrier.
  • the exits of the channels 92 are coupled to a respective cell of a register 93, which is not illuminated as indicated by the shading, and which can be serially read.
  • the clock frequency for this register must be larger, by at least a factor corresponding to the number of columns of a CCD image pick-up element, than the clock signal which displaces the charge within the individual channels.
  • the data stream thus produced on the output of the analog register 93 is amplified in an amplifier 94, after which it is applied to an analog-to-digital converter.
  • FIG. 3 diagrammatically shows how this can be realized.
  • the transport rollers 10, 12 whose circumference amounts to, for example 90 mm, comprise an incremental tacho generator which outputs a fixed number of pulses to a digital electronic circuit 15 during each revolution, for example 18,000 pulses.
  • the circuit 15 produces the clock pulses for the charge displacement in the channels 92 by suitable division of the tacho generator pulses on the output 13.
  • the number of clock pulses depends on the size of an image element, i.e. a cell of the CCD image pick-up element 9.
  • the circuit 15 produces (at least) as many clock pulses as there are channels 92. In the case of 100 channels, therefore, one hundred clock pulses will be required on the output 14 between two clock pulses on the output 13.
  • the storage phosphor record carrier 1, 2 When the storage phosphor record carrier 1, 2 is displaced at a speed of 200 mm per second, the number of revolutions of the transport roller 10 and hence of the transport belt 11, must amount to 2.22 revolutions per second.
  • the pulse frequency on the output 13 then amounts to 2 KHz, resulting in a value of between 200 and 250 KHz for the pulse frequency on the output 14.

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  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Molecular Biology (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Transforming Light Signals Into Electric Signals (AREA)
  • Radiography Using Non-Light Waves (AREA)
  • Measurement Of Radiation (AREA)
  • Facsimile Scanning Arrangements (AREA)
US07/236,575 1987-08-28 1988-08-25 System including a CCD imager device for reading a storage phosphor record carrier Expired - Fee Related US4953038A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3728750 1987-08-28
DE19873728750 DE3728750A1 (de) 1987-08-28 1987-08-28 Vorrichtung zum auslesen eines speicherphosphor-aufzeichnungstraegers

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US4953038A true US4953038A (en) 1990-08-28

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US (1) US4953038A (fr)
EP (1) EP0305010A3 (fr)
JP (1) JPS6472137A (fr)
DE (1) DE3728750A1 (fr)

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5065023A (en) * 1989-09-11 1991-11-12 Quantex Corporation Solid state high resolution photography and imaging using electron trapping materials
US5161038A (en) * 1990-09-19 1992-11-03 Fuji Photo Film Co., Ltd. Apparatus for reading and recording information of characters, images, or the like.
US5420700A (en) * 1990-08-23 1995-05-30 Nikon Corporation Image conversion apparatus having scanning mechanism and optical system on single base
US5483357A (en) * 1993-04-27 1996-01-09 Sharp Kabushiki Kaisha Image scanning device
US5747825A (en) * 1992-11-20 1998-05-05 Picker International, Inc. Shadowgraphic x-ray imager with TDI camera and photo stimulable phosphor plate
EP0859244A1 (fr) * 1997-01-31 1998-08-19 Agfa-Gevaert N.V. Méthode pour générer d'image de rayonnement avec capteurs CCD
US5981953A (en) * 1996-12-04 1999-11-09 Agfa-Gevaert N.V. X-ray image detector and read out apparatus
US5998802A (en) * 1997-01-31 1999-12-07 Agfa-Gevaert Method for obtaining an electrical representation of a radiation image using CCD sensors
DE19859747C1 (de) * 1998-12-23 2000-02-24 Agfa Gevaert Ag Vorrichtung und Verfahren zum Auslesen von in einer Phosphorschicht abgespeicherten Informationen
EP0827324A3 (fr) * 1996-08-27 2000-09-13 Hewlett-Packard Company Balayeur à haute vitesse pour lire des images latentes dans des matériaux phosphorescents à mémoire
WO2002050520A1 (fr) 2000-12-20 2002-06-27 Michel Sayag Procedes de photostimulation et de collecte de lumiere pour plaques images de phosphore de stockage
US20030226985A1 (en) * 2000-04-18 2003-12-11 Fuji Photo Film Co., Ltd. Image information reading apparatus
US20040021101A1 (en) * 2000-06-29 2004-02-05 Essex Electro Engineers, Inc. Method and apparatus for radiographic imaging
US6696698B2 (en) 2000-06-29 2004-02-24 Essex Electro Engineers, Inc. Method and apparatus for radiographic imaging
US6703636B1 (en) * 1999-08-07 2004-03-09 Herbert Gebele Device for reading out information stored in a storage layer
US6774386B2 (en) * 2000-11-07 2004-08-10 Fuji Photo Film Co., Ltd. Image information read-out apparatus
US6861661B1 (en) * 1997-03-06 2005-03-01 Fuji Photo Film Co., Ltd. Radiation image read-out apparatus and image transmission apparatus
US20060180773A1 (en) * 2005-02-15 2006-08-17 Jorg Frankenberger Radiography system and method for recording X-rays in phosphor layers
US20060261297A1 (en) * 2002-01-22 2006-11-23 Richard Gerlach Light distribution system for scanning radiographic images
US20070138419A1 (en) * 2005-12-15 2007-06-21 General Electric Company Computed radiography systems and methods of use
US20070146813A1 (en) * 2005-12-05 2007-06-28 Canon Kabushiki Kaisha Image reading apparatus and method
US9588234B2 (en) 2013-04-22 2017-03-07 Los Alamos National Security, Llc Miniature, mobile X-ray computed radiography system

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0452570B1 (fr) * 1990-04-19 1994-12-28 Agfa-Gevaert N.V. Développeuse et numériseur pour films radiographiques médicaux

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US4369367A (en) * 1979-07-11 1983-01-18 Fuji Photo Film Co., Ltd. Radiation image information read out device
JPS58103267A (ja) * 1981-12-15 1983-06-20 Fujitsu Ltd 読取方式
EP0123942A1 (fr) * 1983-03-31 1984-11-07 Fuji Photo Film Co., Ltd. Procédé de détection d'un signal pour autoradiographie
EP0167747A1 (fr) * 1984-05-09 1986-01-15 Fuji Photo Film Co., Ltd. Dispositif pour la reproduction d'image de rayonnement
US4628356A (en) * 1984-10-15 1986-12-09 Imagex, Inc. Digital X-ray scanner
US4814616A (en) * 1987-04-16 1989-03-21 Fuji Photo Film Co., Ltd. Radiation image recording and read-out apparatus
US4818880A (en) * 1984-03-09 1989-04-04 Fuji Photo Film Co., Ltd. Radiation image read-out apparatus
US4851677A (en) * 1984-12-07 1989-07-25 Fuji Photo Co., Ltd. Apparatus for recording and reproducing image produced by an electron microscope including an optical filter and a deflecting element

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JPS59182364A (ja) * 1983-03-31 1984-10-17 Fuji Photo Film Co Ltd オ−トラジオグラフイ−における信号検出法

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US4369367A (en) * 1979-07-11 1983-01-18 Fuji Photo Film Co., Ltd. Radiation image information read out device
JPS58103267A (ja) * 1981-12-15 1983-06-20 Fujitsu Ltd 読取方式
EP0123942A1 (fr) * 1983-03-31 1984-11-07 Fuji Photo Film Co., Ltd. Procédé de détection d'un signal pour autoradiographie
US4818880A (en) * 1984-03-09 1989-04-04 Fuji Photo Film Co., Ltd. Radiation image read-out apparatus
EP0167747A1 (fr) * 1984-05-09 1986-01-15 Fuji Photo Film Co., Ltd. Dispositif pour la reproduction d'image de rayonnement
US4816679A (en) * 1984-05-09 1989-03-28 Fuji Photo Film Co., Ltd. Radiation image read-out apparatus
US4628356A (en) * 1984-10-15 1986-12-09 Imagex, Inc. Digital X-ray scanner
US4851677A (en) * 1984-12-07 1989-07-25 Fuji Photo Co., Ltd. Apparatus for recording and reproducing image produced by an electron microscope including an optical filter and a deflecting element
US4814616A (en) * 1987-04-16 1989-03-21 Fuji Photo Film Co., Ltd. Radiation image recording and read-out apparatus

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Paul G. Jespers et al., editors, Solid State Imaging, Noordhoff Leyden, 1976, pp. 659 671, Time Delay and Integration Image Sensors , D. F. Barbe. *
Paul G. Jespers et al., editors, Solid State Imaging, Noordhoff-Leyden, 1976, pp. 659-671, "Time Delay and Integration Image Sensors", D. F. Barbe.

Cited By (37)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5065023A (en) * 1989-09-11 1991-11-12 Quantex Corporation Solid state high resolution photography and imaging using electron trapping materials
US5420700A (en) * 1990-08-23 1995-05-30 Nikon Corporation Image conversion apparatus having scanning mechanism and optical system on single base
US5161038A (en) * 1990-09-19 1992-11-03 Fuji Photo Film Co., Ltd. Apparatus for reading and recording information of characters, images, or the like.
US5747825A (en) * 1992-11-20 1998-05-05 Picker International, Inc. Shadowgraphic x-ray imager with TDI camera and photo stimulable phosphor plate
US5483357A (en) * 1993-04-27 1996-01-09 Sharp Kabushiki Kaisha Image scanning device
EP0827324A3 (fr) * 1996-08-27 2000-09-13 Hewlett-Packard Company Balayeur à haute vitesse pour lire des images latentes dans des matériaux phosphorescents à mémoire
US5981953A (en) * 1996-12-04 1999-11-09 Agfa-Gevaert N.V. X-ray image detector and read out apparatus
EP0859244A1 (fr) * 1997-01-31 1998-08-19 Agfa-Gevaert N.V. Méthode pour générer d'image de rayonnement avec capteurs CCD
US5998802A (en) * 1997-01-31 1999-12-07 Agfa-Gevaert Method for obtaining an electrical representation of a radiation image using CCD sensors
US6861661B1 (en) * 1997-03-06 2005-03-01 Fuji Photo Film Co., Ltd. Radiation image read-out apparatus and image transmission apparatus
DE19859747C1 (de) * 1998-12-23 2000-02-24 Agfa Gevaert Ag Vorrichtung und Verfahren zum Auslesen von in einer Phosphorschicht abgespeicherten Informationen
US6369402B1 (en) 1998-12-23 2002-04-09 Agfa-Gevaert Ag Device and method for reading information stored in a phosphor layer
EP1014684A3 (fr) * 1998-12-23 2002-01-16 Agfa-Gevaert Aktiengesellschaft Appareil et méthode pour lire des données enregistrées dans une couche de phosphore
US6703636B1 (en) * 1999-08-07 2004-03-09 Herbert Gebele Device for reading out information stored in a storage layer
US7053398B2 (en) * 2000-04-18 2006-05-30 Fuji Photo Film Co., Ltd. Image information reading apparatus
US20030226985A1 (en) * 2000-04-18 2003-12-11 Fuji Photo Film Co., Ltd. Image information reading apparatus
US20040021101A1 (en) * 2000-06-29 2004-02-05 Essex Electro Engineers, Inc. Method and apparatus for radiographic imaging
US6696698B2 (en) 2000-06-29 2004-02-24 Essex Electro Engineers, Inc. Method and apparatus for radiographic imaging
US6774386B2 (en) * 2000-11-07 2004-08-10 Fuji Photo Film Co., Ltd. Image information read-out apparatus
US20090173899A1 (en) * 2000-12-20 2009-07-09 Michel Sayag Light stimulating and collecting methods and apparatus for storage-phosphor image plates
US6800870B2 (en) 2000-12-20 2004-10-05 Michel Sayag Light stimulating and collecting methods and apparatus for storage-phosphor image plates
US20020090184A1 (en) * 2000-12-20 2002-07-11 Michel Sayag Light stimulating and collecting methods and apparatus for storage-phosphor image plates
WO2002050520A1 (fr) 2000-12-20 2002-06-27 Michel Sayag Procedes de photostimulation et de collecte de lumiere pour plaques images de phosphore de stockage
US20040164257A1 (en) * 2000-12-20 2004-08-26 Michel Sayag Light stimulating and collecting methods and apparatus for storage-phosphor image plates
US20060273262A1 (en) * 2000-12-20 2006-12-07 Michel Sayag Light stimulating and collecting methods and apparatus for storage-phosphor image plates
US7825394B2 (en) 2000-12-20 2010-11-02 Michel Sayag Light stimulating and collecting methods and apparatus for storage-phosphor image plates
US7589341B2 (en) 2000-12-20 2009-09-15 Michel Sayag Light stimulating and collecting methods and apparatus for storage-phosphor image plates
US20060261297A1 (en) * 2002-01-22 2006-11-23 Richard Gerlach Light distribution system for scanning radiographic images
US20060180773A1 (en) * 2005-02-15 2006-08-17 Jorg Frankenberger Radiography system and method for recording X-rays in phosphor layers
US7601973B2 (en) * 2005-02-15 2009-10-13 Agfa-Gevaert Healthcare Gmbh Radiography system and method for recording X-rays in phosphor layers
US20070146813A1 (en) * 2005-12-05 2007-06-28 Canon Kabushiki Kaisha Image reading apparatus and method
US8004724B2 (en) * 2005-12-05 2011-08-23 Canon Kabushiki Kaisha Method and apparatus for image reading with synchronized readout and lighting control
US20080185535A1 (en) * 2005-12-15 2008-08-07 General Electric Company Method for registering a storage phosphor screen
US7550754B2 (en) 2005-12-15 2009-06-23 General Electric Company Method for registering a storage phosphor screen
US7244955B2 (en) 2005-12-15 2007-07-17 General Electric Company Computed radiography systems and methods of use
US20070138419A1 (en) * 2005-12-15 2007-06-21 General Electric Company Computed radiography systems and methods of use
US9588234B2 (en) 2013-04-22 2017-03-07 Los Alamos National Security, Llc Miniature, mobile X-ray computed radiography system

Also Published As

Publication number Publication date
EP0305010A3 (fr) 1993-02-24
JPS6472137A (en) 1989-03-17
EP0305010A2 (fr) 1989-03-01
DE3728750A1 (de) 1989-03-09

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Owner name: U.S. PHILIPS CORPORATION, 100 EAST 42ND STREET, NE

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Effective date: 19880930

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Effective date: 19940831

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Effective date: 19980828

STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362